aside{
    position: fixed;
    right: 16px;
    bottom: 32px;
    z-index: 2000;
    padding-bottom: 20px;
    padding-top: 8px;
    background-color: rgb(255, 255, 255);
    box-shadow: 0 2px 6px 0 rgba(0, 0, 0, 0.07);
    border-radius: 10px;
    width: 80px;
    .main{
        flex-direction: column;
        flex-shrink: 0;
        a{
            box-sizing: content-box;
            display: block;
            // margin-top: 12px;
            padding-top: 12px;
            width: 80px;
            height: 56px;
            position: relative;
            color: #999;
            line-height: 16px;
            font-size: 12px;
            font-style: normal;
            text-align: center;
            cursor: pointer;
        }
        a:before{
            content: "";
            display: block;
            margin: 0 auto;
            width: 40px;
            height: 40px;
            background-image: url('../img/icon-common.svg');
            background-repeat: no-repeat;
        }
        // 购物车
        .shopping_cart::before{
            background-position: 0 -32px;
        }
        // 在线客服
        .online_customer_service::before{
            background-position: -40px -32px;
        }
        // 自助服务
        .self_service::before{
            background-position: -80px -32px;
        }
        // 返回顶部
        .back_to_the_top::before{
            background-position: -120px -32px;
        }

        // hover
        a:hover{
            color: #ca141d;
            &.shopping_cart::before{
                background-position: 0 -72px;
            }
            // 在线客服
            &.online_customer_service::before{
                background-position: -40px -72px;
            }
            // 自助服务
            &.self_service::before{
                background-position: -80px -72px;
            }
            // 返回顶部
            &.back_to_the_top::before{
                background-position: -120px -72px;
            }
        }

        // 隐藏
        .back_to_the_top{
            display: none;
        }
    }
}